Color photographic recording material containing 2-equivalent magenta couplers

ABSTRACT

Stable, color neutral images may be produced by a short time photographic process using a color photographic recording material containing at least one silver halide emulsion layer and at least one 2-equivalent magenta coupler corresponding to formula I on a (preferably reflective) layer support. ##STR1## In the above formula, B denotes a stabilizing group, 
     Y denotes halogen, alkoxy, alkyl, alkylsulphonyl, acylamino, alkoxycarbonyl, carbamoyl, sulphamoyl, amino, trifluoromethyl or cyano, 
     n and o stand for 0, 1 or 2 (but not both 0), 
     p stands for 0 or an integer ≦3-o, 
     q stands for 0 or an integer ≦5-n, and 
     Alk stands for alkyl which may be straight chained or branched and preferably has 1 to 22 carbon atoms and is optionally substituted, e.g. with hydroxy, alkoxy, aroxy or alkoxycarbonyl.

This invention relates to a colour photographic recording materialcomprising at least one silver halide emulsion layer and at least onelayer containing a 2-equivalent magenta coupler of a particularconstitution. The recording material is particularly suitable for theproduction of colour images by a short time photographic process.

By short time photographic process is meant a process which issubstantially shorter than conventional development processes and inwhich mainly the development time may be greatly reduced.

Whereas the development time in conventional processes at temperaturesfrom 25 to 45° C. amounted to 3 minutes or more, the present inventionrelates to a process in which development carried out within the saidtemperature range is completed within a period of from 10 seconds to atthe most 3 minutes. Development preferably takes less than 1 minute.

It is known to use pyrazolone compounds with unsubstituted 4-position ofthe pyrazolone ring (4-equivalent magenta couplers) as magenta couplersin colour photographic, light-sensitive recording materials. Thesecompounds have, however, little colour producing effect and theirstability is unsatisfactory, especially when they are stored undertropical conditions.

So-called 2-equivalent magenta couplers in which a substituent isintroduced into the coupling position of a pyrazolone type coupler andsplit off as a fugitive group at the stage of colour development havebeen used for improving the colour producing effect. Couplers of thistype are described, for example in U.S. Pat. No. 3 311 476, U.S. Pat.No. 3 419 391,U.S. Pat. No.3 617 291 and U.S. Pat. No. 3 926 631. Othermagenta couplers in which a substituent is attached to the couplingposition by a sulphur atom are described in U.S. Pat. No. 3 214 437,U.S. Pat. No. 4 032 346, U.S. Pat. No. 3 227 554 and U.S. Pat. No. 3 701783, JA 34044/78 and DE-A-29 44 601.

Chromogenic development converts 4-equivalent magenta couplers of thepyrazolone series into azomethine dyes which are rendered sufficientlystable for photographic recording materials by means of suitable knownstabilizers such as derivatives of chroman, hydroquinone, piperidine,etc.

-S-Alkyl and -S-aryl fugitive groups attached to such couplers generallyimpair the light-resistance of the resulting azomethine dyes to such anextent that they cannot be used in photographic recording materials evenwhen known stabilizers and light-protective agents are used. Exceptionsare, for example, couplers of the type described in DE-A-36 22 007 andDE-A-31 31 926 which carry specially substituted thiophenols as fugitivegroups.

Although the last-mentioned couplers give rise to dyes with sufficientstability to light, they cannot be used in photographic materials forshort time processing because the formation of dyes from them isincomplete during the time of development. In addition, these couplersare unsuitable for reasons of cost because the synthesis of the fugitivegroups required is complicated and cost intensive.

Moreover, many of the thio compounds released in the coupling reactionof such 2-equivalent couplers are not photographically harmless. Theyare liable to interfere with further development and inhibit the bleachfixing carried out after development. The latter can be recognized by apermanent Ag° image.

It is an object of the present invention to provide 2-equivalent magentcouplers which

1. are usable for colour photographic materials viewed by reflectedlight, i.e.

(a) give rise to dyes with suitable absorption properties,

(b) have a high colour producing activity,

(c) are highly stable both in dry and in moist heat,

(d) have a high formaldehyde stability after development,

(e) do not inhibit bleaching in bleach fixing baths, especially afterprolonged use, and

(f) form dyes which have excellent resistance both to dry and to moistheat and to the action of light,

2. contain groups which are readily accessible and rapidly split off inthe coupling reaction with oxidized colour developers,

3. are comparatively unaffected by the usual changes in the pH of thecolour developer and

4. enable the formation of dyes to be completed or at least to asufficient extent for use in photographic materials by the timedevelopment in a short time process is terminated.

It has now been found that these aims can be realized by means of2-equivalent magenta couplers having the structure shown below.

The present invention relates to a colour photographic recordingmaterial having at least one silver halide emulsion layer and at leastone layer containing a 2-equivalent magenta coupler corresponding toformula I ##STR2## wherein

B denotes a stabilizing group,

Y denotes halogen, alkoxy, alkyl, alkylsulphonyl, acylamino,alkoxycarbonyl, carbamoyl, sulphamoyl, amino, trifluoromethyl or cyano,

n and o stand for 0. 1 or 2 (but not both for 0).

p stands for 0 or an integer<3-o,

q stands for 0 or an integer<5-n and

Alk stands for a straight chained or branched alkyl preferablycontaining 1-22 carbon atoms, and optionally substituted, e.g. withhydroxy, alkoxy, aroxy or alkoxycarbonyl.

Acylamino is an acylated amino group in which acyl is derived fromaliphatic or aromatic carboxylic or sulphonic acids, carbamic acids orcarbonic acid semiesters. The term "acylamino" also includes cycloimido.

Carbamoyl and sulphamoyl include carbamoyl and sulph, amoyl groups whichare monosubstituted or disubstituted on the N atom, e.g. with alkyl,aralkyl or aryl. Amino may similarly be monosubstituted or disubstitutedor it may be a cyclic amino group (e.g. pyrrolidino, piperidino, ormorpholino).

Alkyl groups in the alkylsulphonyl, acylamino, alkoxycarbonyl, carbamoyland sulphamoyl may have 1 to 18 carbon atoms and are optionally branchedand/or substituted.

Examples of suitable stabilizing groups B include compoundscorresponding to the following formulae II, III and IV ##STR3## andtheir ethers which are attached by the OH group or one of thesubstituents R¹ to R²³ to the coupler molecule either by a direct bondor by a bridging member.

In formulae II to IV, the substituents have the following meanings:

R¹ to R⁵ denote hydrogen, halogen, alkyl, alkoxy, aryl, aryloxy,carboxy, sulpho, alkoxycarbonyl, alkylamino, carbamoyl, sulphamoyl,alkylsulphonyl or arylsulphonyl

R⁶ to R²³ denote hydrogen or alkyl.

Halogen in particular denotes fluorine, chlorine or bromine.

Alkyl in particular denotes C₁ -C₁₈ -alkyl which is optionally branched.

Alkoxy in particular denotes C₁ -C₁₂ -alkoxy.

Acylamino in particular denotes C₁ -C₁₈ -alkylcarbonylamino, C₁ -C₁₈-alkylsulphonylamino and C₁ -C₁₈ -alkoxycarbonylamino as well asbenzoylamino and benzene sulphonylamino.

Alkoxycarbonyl in particular denotes C₁ -C₁₈ -alkoxycarbonyl.

Carbamoyl and sulphamoyl include carbamoyl and sulphamoyl groups whichare mono-substituted or di-substituted on the nitrogen atom (e.g. withC₁ -C₂ -alkyl).

Aryl denotes in particular phenyl, aryloxy denotes in particular phenoxyand the phenyl ring may in each case be further substituted.

Bridging members may in particular be C₁ -C₁₈ -alkylenecarbonylaminogroups.

Preferred 2-equivalent magenta couplers according to the presentinvention correspond to formula V ##STR4## wherein

R²⁴ denotes chlorine,

R²⁵ denotes hydrogen, methoxy, chlorine, methyl, cyano or B₁,

R²⁶ denotes chlorine or methyl,

R²⁷ denotes hydrogen, di-C₁ -C₆ -alkylaminocarbonyl, C₁ -C₆-alkylcarbonylamino or B₁,

R²⁸ denotes hydrogen, chlorine, CN or B₁,

R²⁹ denotes chlorine or methoxy, and either R²⁵ or R²⁷ or R²⁸ has themeaning of B₁ and

B₁ denotes a group corresponding to the following formula ##STR5##wherein

R³⁰ denotes hydrogen or C₁ -C₁₂ -alkyl,

R³¹ denotes hydrogen, C₁ -C₈ -alkoxy, hydroxy, C₁ -C₈ -alkylcarbonyloxyor C₁ -C₈ -alkyl,

R³² denotes hydrogen, hydroxy, C₁ -C₁₂ -alkoxy or C₁ -C₈ -alkyl and

R³³ denotes hydrogen or C₁ -C₈ -alkyl.

The substituents in formula V preferably have the following meanings:

R²⁴, R²⁵, R²⁶ and R^(25:) chlorine and

R^(27:) a group corresponding to the following formula ##STR6## whereinRJ³⁴ and R³⁵ stand for hydrogen or C₁ -C₁₂ -alkyl.

The following are suitable groups of the structure ##STR7##

The following are examples of suitable groups B: ##STR8##

The basic structure of the couplers may in particular correspond to thefollowing formulae: ##STR9##

The compounds entered in Table are particularly preferred couplers K.

    ______________________________________                                                 Fugitive              Basic                                                   group       Stabilizing                                                                             Coupler                                        K        A           group     structure                                      ______________________________________                                         1       A1          B1        C1                                              2       A1          B13       C1                                              3       A2          B14       C1                                              4       A3          B1        C1                                              5       A3          B2        C8                                              6       A3          B3        C1                                              7       A3          B10       C3                                              8       A3          B13       C1                                              9       A4          B1        C4                                             10       A4          B4        C5                                             11       A4          B13       C1                                             12       A5          B6        C2                                             13       A5          B13       C7                                             14       A6          B1        C4                                             15       A6          B3        C6                                             16       A6          B8        C1                                             17       A6          B13       C4                                             18       A7          B14       C1                                             19       A7          B15       C7                                             20       A8          B2        C8                                             21       A8          B14       C7                                             22       A9          B1        C4                                             23       A10         B1        C1                                             24       A10         B13       C1                                             25       A11         B13       C6                                             26       A12         B1        C4                                             ______________________________________                                    

The 2-equivalent magent couplers according to the invention are preparedby reaction of the corresponding 4-equivalent couplers with mercaptocompounds by methods (or methods analogous thereto) described, forexample, in U.S. Pat. No. 3 227 554, Research Disclosure 13806 (October1975), DE-A-3 241 886, DE-A-3 622 007 and DE-A-3 644 406, for example asfollows:

1. An alkylmercaptan or a corresponding disulphide is converted into asulphenylhalide by means of a halogenating agent (for example, chlorine,bromine, sulphuryl chloride, N-bromosuccinimide, etc.) and then reactedwith a 4-equivalent coupler in the presence of a catalyst. This methodmay also be carried out by the addition of a halogen (i.e. halogen inthe form of a gas or a liquid) to a mixture of an alkylmercaptan phenolderivative or a 4-equivalent coupler (U.S. Pat. No. 3 227 554).

2. The active position of a 4-equivalent coupler is treated with ahalogenating agent, optionally after previous protection of free aminogroups by acylation (for example, insertion of an acetyl or anethoxycarbonyl group), and the resulting compound is reacted with analkylmercaptan in the presence of a basic catalyst or in the absence ofa catalyst. The desired 2-equivalent coupler is obtained by removal ofthe protective group (JA-OS 91862/77).

The colour photographic recording material according to this inventionmay be processed in the usual manner by colour development, bleachingand fixing (or bleach fixing). Magenta dye images with excellentspectral and stability properties are obtained. The advantages of thecolour photographic recording material according to the invention areparticularly marked in so-called short time photographic processes, i.e.processes in which in particular the step of development, e.g. attemperatures from 25 to 45° C. takes no longer than 2 minutes,preferably not longer than 1 minute. The invention therefore alsorelates to a short time photographic process for the production ofcolour photographic images by chromogenic development followed bybleaching and fixing (or bleach fixing), using the colour photographicrecording material described here. The processing steps followingchromogenic development are advantageously also greatly reduced in timecompared with those of conventional processes.

The colour photographic recording material according to the inventioncontains at least one light-sensitive silver halide emulsion layer,preferably a sequence of several such light-sensitive silver halideemulsion layers, optionally with light-insensitive layers of binderarranged between the said silver halide emulsion layers. According tothe present invention, a 2-equivalent magenta coupler of formula I isassociated with at least one of the light-sensitive silver halideemulsion layers present.

The halide present in the light-sensitive silver halide emulsions usedin the light-sensitive layers may be chloride, bromide, iodide ormixtures thereof. The emulsions are preferably chloride-rich emulsionswith a bromide content of less than 1 mol-%. Since materials containingsuch silver halide emulsions are particularly suitable for the shorttime photographic process, the present invention also relates to acolour photographic recording material having at least onelight-sensitive silver halide emulsion layer in which more than 99% ofthe silver halide consists of silver chloride and with which a2-equivalent magenta coupler of formula I and optionally also an oilformer are associated.

The emulsions may be heterodisperse or monodisperse emulsions,preferably with an average grain size of from 0.3 μm to 1.2 μm. Thesilver halide grains may have a layered grain structure.

The emulsions may be chemically and/or spectrally sensitized in theusual manner and may also be stabilized with suitable additives.Suitable chemical sensitizers, spectral sensitizing dyes and stabilizersare described, for example, in Research Disclosure 17643 (December1978): see in particular Chapters III, IV and VI.

The colour photographic recording material according to the inventionpreferably contains at least one light-recording silver halide emulsionlayer for each of the three spectral regions, red, green and blue, whichlayer is spectrally sensitized by suitable sensitizing dyes in knownmanner.

A light-insensitive interlayer is generally arranged between layerswhich differ in their spectral sensitivity. This interlayer may containsubstances for preventing accidental diffusion of developer oxidationproducts. When a material contains several silver halide emulsion layersof the same spectral sensitivity, these may be arranged adjacent to oneanother or they may be separated by a light-sensitive layer of adifferent spectral sensitivity (DE-A-19 58 709, DE-A-25 30 645, DE-A-2622 922).

Colour photographic recording materials according to the inventionnormally contain colour couplers for producing the different partialcolour images in cyan, magenta and yellow in spatial and spectralassociation with the silver halide emulsion layers of the differentspectral sensitivities, the 2-equivalent magenta coupler according tothe present invention being generally associated with a green-sensitivesilver halide emulsion layer.

By "spatial association" is meant that the colour coupler is in suchspatial relationship to the silver halide emulsion layer that they arecapable of interacting to give rise to an imagewise correspondencebetween the silver image resulting from development and the colour imageproduced from the colour coupler. This is generally achieved byintroducing the colour coupler into the silver halide emulsion layer orinto an optionally light-insensitive layer of binder adjacent to saidsilver halide emulsion layer.

By "spectral association" is meant that the spectral sensitivity of eachof the light-sensitive silver halide emulsion layers and the colour ofthe partial image produced from the spatially associated colour couplerare in a certain relationship to one another, each of the spectralsensitivities (red, green, blue) having a different colour of thecorresponding partial colour image associated therewith (in general e.g.the colours cyan, magenta and yellow, in this sequence).

In preferred embodiments, therefore, red-sensitive silver halideemulsion layers have at least one non-diffusible colour couplerassociated with them for producing the cyan partial colour image,generally a coupler of phenol or α-naphthol series, and green-sensitivesilver halide emulsion layers have at least one non-diffusible colourcoupler associated with them for producing the magenta partial colourimage; for the latter, other magenta couplers, e.g. of the indazolone orpyrazoloazole series. may be used in addition to the 2-equivalentmagenta couplers used according to the invention.

The blue-sensitive silver halide emulsion layers have at least onenon-diffusible colour coupler associated with them for producing theyellow partial colour image, generally a colour coupler containing anopen chain keto methylene group. Colour couplers of this type are knownin large numbers and have been described in numerous PatentSpecifications; see, for example, the publication "Farbkuppler" by W.PELZ in "Mitteilungen aus den Forschungslaboratorien der Agfa,Leverkusen/Munchen", Volume III, page 111 (1961) and the publication byK.VENKATARAMAN in "The Chemistry of Synthetic Dyes", Vol.4. 341 to 387,Academic Press (1971).

Conventional layer supports may be used for the recording materialsaccording to the invention, e.g. supports of cellulose esters such ascellulose acetate or of polyesters. Paper supports are also suitable,and these may be coated, e.g. with polyolefines, in particular withpolyethylene or polypropylene; see Research Disclosure 17643, ChapterXVII. A light-reflective layer support is preferably used.

The protective colloids or binders used for the layers of the recordingmaterial may be any of the conventional hydrophilic film-formingsubstances, e.g. proteins, in particular gelatine. Casting auxiliariesand plasticizers may be used: see Research Disclosure 17643, ChaptersIX, XI and XII.

The layers of the photographic material may be hardened in the usualmanner, for example with hardeners containing at least two reactiveoxirane, aziridine or acryloyl groups. The layers may also be hardenedby the process according to DE-A-22 18 009. Further, the photographiclayers or colour photographic multilayered materials may be hardenedwith hardeners of the diazine, triazine or 1,2-dihydroquinoline seriesor with vinylsulphone type hardeners. Other suitable hardeners are knownfrom DE-A-24 39 551, DE-A-22 25 230 and DE-A-24 39 551 and from ResearchDisclosure 17643, Chapter X. The stabilizing effect of the oil formersaccording to the invention is particularly marked when hardeners whichactivate carboxyl groups are used, e.g. carbamoyl pyridinium salts orcarbamoyl oxypyridinium salts.

In addition to the above-mentioned components, the colour photographicrecording material according to the present invention may contain otheradditives, for example anti-oxidants, dye stabilizing agents andsubstances which influence the mechanical and electrostatic properties.It is also advantageous to use UV absorbent compounds in one or more ofthe layers of the recording material, preferably one of the upperlayers, for the purpose of reducing or preventing the adverse effect ofUV light on the colour images produced with the colour photographicmaterial according to the invention. Suitable UV absorbents aredescribed, for example. in U.S. Pat. No. 3 253 921. DE-C-2 036 719 andEP-A-0 057 160.

Other suitable additives are indicated in Research Disclosure 17643 andin "Product Licensing Index" of December 1971, pages 107-110.

Examples of suitable colour developer substances for the materialaccording to the invention include in particular those of thep-phenylenediamine series, e.g. 4-amino-N,N-diethyl-anilinehydrochloride, 4-amino-3-methyl-N,N-diethyl-aniline hydrochloride,4-amino-3-methyl-N-ethyl-N-β-(methanesulphonamido)-ethylaniline sulphatehydrate, 4-amino-3-methyl-N-ethyl-N-β-hydroxyethyl aniline sulphate,4-amino-N-ethyl-N-(2-methoxyethyl)-m-toluidine-di-p-toluene sulphonicacid and N-ethyl-N-β-hydroxyethyl-p-phenylenediamine. Other suitablecolour developers are described, for example, in J.Amer.Chem.Soc. 73,3100 (1951). Suitable formulations for colour developers and additivesfor these developers are described, for example, in G. Haist, ModernPhotographic Processing, 1979, John Wiley and Sons, New York, Vol.2,pages 545 et seq.

The colour developer bath used is preferably substantially free frombenzyl alcohol and/or substantially free from bromide ions.

After colour development, the material is bleached and fixed in theusual manner. Bleaching and fixing may be carried out separately ortogether. The usual bleaching agent compounds are used, e.g. Fe³⁺ saltsand Fe³⁺ complex salts such as ferricyanides, dichromates, water-solublecobalt complexes, etc. Iron-III complexes of aminopolycarboxylic acidsare particularly preferred, especially e.g. the complexes of ethylenediaminotetracetic acid, nitrilotriacetic acid, iminodiacetic acid,N-hydroxyethyl ethylene diaminotriacetic acid and alkyliminodicarboxylicacids and of the corresponding phosphonic acids. Persulphates are alsosuitable bleaching agents.

The material is generally washed after this development has beencompleted but effluent saving processes are known in which stabilizingbaths are used instead of washing baths.

The process may also be rendered more rational by carrying thewash-water and the stabilizing bath in counter-current: see DE-A-29 20222, DE-A-31 23 771, EP-A-0 182 566,EP-A-0 185 371, EP-A-0 186 158,EP-A-0 186 169, EP-A-0 186 504 and EP-A-206 148.

EXAMPLE 1

Colour photographic recording materials were prepared as describedbelow.

(a) Preparation of the colour coupler emulsions

8 mmol of colour coupler are dissolved in equal parts by weight ofdibutylphthalate and three times the quantity by weight of ethyl acetatein the presence of 0.15 g of sulphosuccinic acid dioctyl ester at atemperature of 50 to 75° C. The solution is then stirred into 150 g of a7.5% by weight aqueous gelatine solution which is at a temperature ofabout 40° C.

(b) Preparation of the colour photographic recording materials which areto be tested

The emulsion prepared under a) is mixed with a silver halide emulsioncontaining 8.2 g of silver in the form of silver bromide, 9.2 g ofgelatine and 0.04 g of sodium dodecylbenzene sulphonate. The totalvolume is adjusted with water to 350 ml. The casting solution thusprepared is cast on a layer support of cellulose triacetate (0.8 g ofAg/m²).

(c) Processing and assessment

After drying, the material is exposed behind a graduated wedge andcolour developed as follows:

1. Developer bath - 3.25 min

8,000 ml of distilled water, 47 g(N-ethyl-N-β-hydroxyethylamino)-2-merhyl aniline sulphate

25 g of hydroxyl ammonium sulphate

39 g of sodium sulphite

15.5 g of sodium bicarbonate

335 g of potassium carbonate

13.5 g of potassium bromide

made up to 10 1 with distilled water; pH 10.

2. Bleach fixing bath - 1.5 min

35 ml of ammonia solution (28% by weight)

30 g of ethylene diaminotetracetic acid (EDTA),

15 g of Na₂ SO₃,

100 g of ammonium thiosulphate,

60 g of sodium-(EDTA)-iron-III complex

made up to 1,000 ml with water, pH 7.

3. Washing - 3 min.

Table 1 shows the colour couplers used and the fresh sensitometricvalues obtained with these couplers.

The Table also shows in the last two columns the densities measured inpercent in the blue and red spectral region at maximum density of thesamples. ##STR10##

                  TABLE 1                                                         ______________________________________                                                       Sensi-                % side density                                          tivity   Colour       at D.sub.max                             Sample                                                                              Coupler  [DIN]    yield Gamma  blue  red                                ______________________________________                                        A     M-1      19.8     1.72  0.85   13    10                                 B     M-2      17.2     1.18  0.53   14     9                                 C     M-3      21.0     2.04  0.98    9     7                                 D     M-4      20.6     1.96  0.93   10    10                                 E     M-5      23.1     2.78  2.16   29    27                                 F     M-6      23.2     3.40  2.45   10     8                                 G     K-8      23.3     3.28  2.20    9    10                                 H     K-11     23.7     3.18  2.12   10     9                                 J     K-13     22.8     3.05  2.35   11    11                                 K     K-18     23.2     3.10  2.20    9    10                                 L     K-21     23.4     3.15  2.34   11    10                                 M     K-26     22.9     2.95  2.18   13    12                                 ______________________________________                                    

Example 1 demonstrates the sensitometric advantages of 2-equivalent3-anilinopyrazolone couplers (Samples E to M) compared with 2- and4-equivalent 3-acylamino- and 4-equivalent 3-anilino-pyrazolonecouplers. It also indicates the high colour yields and steep gradationsof the couplers according to the invention but also of the Comparisoncouplers M-5 and M-6.

EXAMPLE 2

Samples C to M of Example 1 and Samples N to X (see below) were exposedwith a grey wedge and developed as described below.

Samples N to X have the same composition as Samples C to M and inaddition contain an emulsion which corresponds to the colour coupleremulsion but contains 8 mmol of stabilizer S-1 instead of the colourcoupler. ##STR11##

In addition, Samples Y (corresponding to C to M) and Z (corresponding toN to X) are prepared, Y containing Comparison coupler M-7 and Zcontaining Comparison coupler M-7 and in addition S-1: ##STR12##

The samples obtained after Development 2 were measured in the freshstate and again after 4 weeks.

The samples obtained after Development 1 were covered with a UVprotective foil and exposed to 7.2-10⁶ 1×·h in a Xenon test apparatus.

The results are summarized in Table 2.

Development 1 (E1)

(a) Colour developer-3.5 min=33° C.

15 ml of benzyl alcohol

15 ml of ethylene glycol

3 g of hydroxylamine sulphate

4.5 g of 3-methyl-4-amino-N-ethyl-N-(β)-methanesulphonamidoethyl)-aniline sulphate

32 g of K₂ CO₃

2 g of K₂ SO₃

0.6 g of KBr

1 g of the disodium salt of 1-hydrozyethane-1,1-diphosphonic acid

made up to 1,000 ml with water; pH 10.2.

(b) Bleach fixing bath - 1.5 min

35 ml of ammonia solution (28%)

30 g of EDTA

15 g of Na₂ SO₃

100 g of ammonium thiosulphate

60 g of sodium-(EDTA)-iron-III complex

made up to 1,000 ml with water; pH 7.

(c) Washing - 3 min

Development 2 (E2)

(a) Colour developer - 45 g - 35° C.

    ______________________________________                                        Triethanolamine           9.0    g                                            N,N-Diethylhydroxylamine  6.0    g                                            Diethyleneglycol          0.05   g                                            3-Methyl-4-amino-N-ethyl-N-methane                                                                      6.0    g                                            sulphonamidoethyl-aniline sulphate                                            Potassium sulphite        0.2    g                                            Triethylene glycol        0.05   g                                            Potassium carbonate       22     g                                            Potassium hydroxide       0.4    g                                            Disodium salt of ethylenediamino                                                                        2.2    g                                            tetracetic acid                                                               made up with water to 1000 ml; pH 9.2                                         ______________________________________                                    

(b) Bleach fixing bath - 45 s - 33° C.

    ______________________________________                                        Ammonium thiosulphate   75     g                                              Sodium hydrogen sulphite                                                                              13.5   g                                              Ammonium acetate        2.0    g                                              Ethylene diaminotetracetic acid                                                                       57     g                                              (iron-ammonium salt)                                                          Ammonia (25%)           9.5    g                                              Acetic acid                                                                   ______________________________________                                    

c. Washing - 2 min-33° C.

                  TABLE 2                                                         ______________________________________                                                                       % Reduction in                                                                Xenon test with                                                     E2        UV protection                                  E1        fresh      4 weeks   7.2 · 10.sup.6 1x · h        Sample                                                                              FA      FA     G2    FA   G2   at D = 0.5                                                                             1.5                             ______________________________________                                        C     2.03    1.98   2.10  1.97 2.12 36       24                              D     2.11    2.13   2.20  2.15 2.16 30       23                              E     2.48    2.16   3.94  2.71 5.42 46       41                              F     2.65    2.51   4.98  2.62 5.05 48       47                              G     2.69    2.64   4.93  2.68 5.02 32       24                              H     2.58    2.52   4.85  2.58 4.96 37       25                              J     2.48    2.43   4.72  2.53 4.88 36       22                              K     2.62    2.49   5.05  2.58 5.20 33       24                              L     2.55    2.51   5.10  2.61 5.25 35       22                              M     2.51    2.42   5.05  2.52 5.12 34       24                              N (C) 2.08    2.05   2.15  2.06 2.14 22       16                              O (D) 2.10    2.15   2.24  2.17 2.23 20       16                              P (E) 2.32    1.98   3.74  2.45 4.95 36       30                              R (F) 2.60    2.45   4.75  2.55 4.86 38       36                              ______________________________________                                    

Example 2, Development 2, shows the sensitometric advantages of2-equivalent pyrazolone couplers containing fugitive groups according tothe invention compared with couplers containing arylthio fugitive groupsIt is seen that measured by the sensitometry, only the couplersaccording to the invention and Comparison coupler M-6 can be used inmaterials for short time photographic processes.

If one considers the light resistance of the dyes produced from thesecolour couplers by chromogenic development, it is clear that only thedyes produced from the colour couplers according to the invention haveresistances to light equal to those obtained under comparable conditionsfrom 4-equivalent couplers or from 2-equivalent couplers containingspecial arylthio fugitive groups (samples X,Y). It is also seen that thedyes obtained from the coupler M-6 (Sample F) which is not according tothe invention cannot achieve the level of stability to light of thecouplers according to the invention even when stabilizer S-1 (Sample R)is added. The same also applies to other stabilizers known in the art.

Summarizing Example 2 shows that in materials for short time processing,only the 2.equivalent couplers according to the invention may be used byvirtue of their sensitometric properties and the stability of their dyesto light.

EXAMPLE 3

A coupler emulsion containing the 4-equivalent magenta coupler M-3 in aquantity providing a ratio by weight of AgNO₃ /coupler of 1:0.9 is addedto a green-sensitized and stabilized AgCl emulsion having a silvernitrate/gelatine ratio of 1:1.

To prepare the coupler emulsion, 4 g of gelatine were dissolved in 50 mlof water and to this solution was added 0.5 g ofdodecylbenzenesulphonate An oil phase consisting of 10 g of coupler M-3,4 g of stabilizer S.2 and 2 g of stabilizer S-3, 4 g oftricresylphosphate and 3.5 g of dinonylphthalate dissolved in 20 ml ofethyl acetate was emulsified in this solution by means of a high speedstirrer with a powerful shearing action. 2.06 g of gelatine (as 10%solution) was then added to the emulsion per 1 g of AgNO₃ and theemulsion was diluted with water so that 1,000 ml of emulsion contained12.5 g of AgNO₃. The emulsion was then applied in a wet layer thicknessof 36 μm to a paper which was coated with polyethylene on both sides.

Another layer, containing 1 g of gelatine per m² and containing thehardener CAS Reg. No 65411-60-1 in a quantity of 5% by weight, based onthe total quantity of gelatine, was also applied

The resulting material was cut up and exposed behind a ∛2 step wedge.Development was carried out as described in Example 2, Development 2.

Step wedges were also prepared similarly with couplers M-6, M.8, M-9 andthe coupler according to the invention K-8.

The following values (Table 3) were obtained from measuring thesensitivity E (D =0.6) and shoulder gradation G₂ and maximum densityD_(max) immediately after development:

                  TABLE 3                                                         ______________________________________                                        Coupler    E            G      D.sub.max                                      ______________________________________                                        M-3        1.74         3.04   2.50                                           M-6        1.68         4.82   2.35                                           M-8        1.78         4.54   1.71                                           K-8        1.66         4.93   2.33                                           ______________________________________                                    

The following values were measured (Table 4) after the developed wedgeshad been stored for 1 week/2 weeks:

                  TABLE 4                                                         ______________________________________                                        Coupler  E             G.sub.2  D.sub.max                                     ______________________________________                                        M-3      1.74/1.74     3.04/3.03                                                                              2.50/2.50                                     M-6      1.68/1.68     4.89/4.89                                                                              2.49/2.50                                     M-9      1.80/1.80     5.49/5.49                                                                              2.45/2.44                                     K-8      1.66/1.66     4.97/4.97                                                                              2.51/2.50                                     ______________________________________                                    

The wedges are then exposed behind a UV filter in a Xenotest apparatusat 10×10⁶ l×h. The following values were obtained for the percentagereduction in density for density 1.1:

    ______________________________________                                                M-3          -23%                                                             M-6          -57%                                                             M-8          -21%                                                             M-9          -31%                                                             K-8          -27%.                                                    ______________________________________                                    

The results show that only coupler K-8 according to the invention may beused as 2-equivalent coupler for short time processing. The steepgradation is very marked compared with the 4-equivalent coupler M-3.Comparison couplers M-8 and M-9 show too great a sensitometric change instorage. Comparison coupler M-6,which only shows a small sensitometricchange, must be eliminated on account of its very poor dye stability.##STR13##

EXAMPLE 4

The following layers were applied to a layer support of paper which wascoated with polyethylene on both sides. The quantities are based on 1m².

1. A substrate layer of 200 mg of gelatine with the addition of KNO₃ andchrome alum

2. A blue-sensitive silver chloride emulsion layer of 600 mg of AgNO₃containing 2,100 mg of gelatine, 1.1 mmol of yellow coupler, 27.7 mg of2,5-dioctylhydroquinone and 1,200 mg of tricresylphosphate

3. An interlayer of 1,300 mg of gelatine, 80 mg of2,5-dioctylhydroquinone and 100 mg of tricresylphosphate

4. A green-sensitive silver chloride emulsion layer of 530 mg of AgNO₃containing 750 mg of gelatine, 0.625 mmol of the magenta coupler shownin Table 3 below 118 mg of α(3-t-butyl-4-hydroxyphenoxy)-myristic acidethyl ester, 43 mg of 2,5-dioctylhydroquinone and oil former as shown inTable 3,

5. An interlayer of 1550 mg of gelatine, 285 mg of the UV absorbentTinuvin 343®,k 80 mg of dioctylhydroquinone and 650 mg oftricresylphosphate,

6. A red-sensitive silver halide emulsion layer of 400 mg of AgNO₃containing 1470 mg of gelatine, 0.780 mmol of cyan coupler, 285 mg ofdibutylphthalate and 122 mg of tricresylphosphate,

7. A protective layer of 1200 mg of gelatine and 134 mg of Tinuvin 343®and

8. A hardening layer of 400 mg of gelatine and 400 mg of an instanthardener [CAS REg. No. 65411-60-1].

The following couplers were used in layers 2 and 6: ##STR14##

The quantities of coupler and silver halide in layer 4 are applicablewhen the magenta coupler is a 4-equivalent coupler. When a 2-equivalentmagenta coupler is used, it is applied in a quantity of 0.5 mmol and thequantity of silver chloride applied corresponds to 420 mg of AgNO₃.

Various recording materials differing only in layer 4 were prepared, asshown in Table 3 below:

                  TABLE 3                                                         ______________________________________                                        Material            Magenta coupler                                           ______________________________________                                        1                   M-3                                                       2                   M-4                                                       3                   M-5                                                       4                   M-7                                                       5                   M-6                                                       6                   K-4                                                       7                   K-8                                                       8                   K-13                                                      9                   K-16                                                      10                  K-26                                                      ______________________________________                                    

The materials were exposed behind a grey wedge and developed by bothdevelopment processes (Development 1 and Development 2) described inExample 2.

When long time processing was employed, all the materials were found tobe neutral over the whole density range, i.e. no colour change was foundat the transition to higher densities.

A different result was obtained from short time processing. At very lowdensities, the samples were again found to be neutral grey. Withincreasing density, however, materials 3 and 4 tipped over and in theregion of maximum colour density they were bright green. It was onlyafter several days' storage at room temperature or 2 hours' storage at65° C. that these materials were also neutral in colour.

The other materials, i.e. materials 1 and 2 (4-equivlent couplers) andmaterials 5 to 10 (2-equivalent couplers) containing small amounts ofsilver and coupler were found to be neutral grey after processing.

Materials 3 and 5 differed from all the other materials in their poorbleaching response when exposed (as in Example 2); the grey wedgesunderwent discolouration after some time and turned a dirty green.

We claim:
 1. Colour photographic recording material having at least onesilver halide emulsion layer arranged on a layer support and at leastone layer containing a 2-equivalent magenta coupler corresponding toformula V ##STR15## wherein Alk denotes straight chained or branchedalkyl or straight chained or branched alkyl substituted with hydroxy,alkoxy, aroxy or alkoxycarbonyl;R²⁴ denotes chloro; R²⁵ denoteshydrogen, methoxy, chloro, methyl, cyano or B_(1;) R²⁶ denotes chloro ormethyl; R²⁷ denotes hydrogen, di-C₁ -C₆ -alkylaminocarbonyl, C₁ -C₆-alkylcarbonylamino or B_(1;) R²⁸ denotes hydrogen, chloro, CN or B_(1;)R²⁹ denotes chloro or methoxy and either R²⁵ or R²⁷ or R²⁸ has themeaning of B₁ and B₁ denotes a residue of the formula ##STR16## whereinR³⁰ denotes hydrogen or C₁ -C₁₂ -alkyl; R³¹ denotes hydrogen, C₁ -C₈-alkoxy, hydroxy, C₁ -C₈ -alkylcarbonyl or C₁ -C₈ -alkyl; R³² denoteshydroxy or C₁ -C₁₂ -alkoxy and R³³ denotes hydrogen or C₁ -C₈ -alkyl. 2.Recording material according to claim 1, characterised in that more than99 mol-% of the silver halide in the silver halide emulsion layercontaining the 2-equivalent magenta coupler is silver chloride and lessthan 1 mol-% is silver bromide.
 3. Recording material according to claim2 characterised in that the layer support is a reflective layer support.